Location: Wheat Health, Genetics, and Quality Research
Project Number: 2090-22000-020-000-D
Project Type: In-House Appropriated
Start Date: Mar 28, 2022
End Date: Mar 27, 2027
Objective:
This project will work to achieve the following objectives over the next five years:
1) Monitor and characterize stripe rust pathogen populations towards the development of appropriate measures to reduce damage on wheat and barley.
2) Enhance resistance in wheat and barley cultivars for effective stripe rust control.
Approach:
For Objective 1 (Monitor and characterize stripe rust pathogen populations towards the development of appropriate measures to reduce damage on wheat and barley), we will use our models for the Pacific Northwest (PNW) to predict stripe rust epidemic levels. To monitor and mange stripe rust, we will conduct field survey and provide rust updates and recommendations to growers to implement appropriate control measures. To identify stripe rust races, rust samples will be collected from cereals (wheat, barley, rye, and triticale) and various grasses by collaborators and ourselves during surveys, and the isolates will be characterized for virulence using our standard protocols of our program. To identify population changes, we will use a standard set of 14 SSR markers to characterize stripe rust isolates. We will also identify SNP markers associated to avirulence genes and converted them into KASP markers. KASP markers with the highest value of correlation coefficient will be selected to establish a set of KASP markers for avirulence genes.
For Objective 2 (Enhance resistance in wheat and barley cultivars for effective stripe rust control), we will screen wheat, barley, and triticale lines from breeding programs throughout the U.S for developing new resistant varieties. To determine the stripe rust resistance levels, potential yield losses, and response to fungicide application of commercially grown varieties, each year we will evaluate 23 winter and 23 spring wheat varieties from the Pacific Northwest, plus a susceptible check in each nursery. The results of these tests will be used to guide growers for selecting resistance varieties and appropriately use of fungicides. For identifying new geremplasm and stripe rust resistance genes, we will complete the studies of mapping and identifying stripe rust resistance in three wheat panels using the genome-wide association study (GWAS) approach. We will also focus on mapping and identifying genes for resistance to stripe rust in the 40 crosses made from 40 winter wheat varieties crossed with susceptible AvS. We have identified 233 SNP markers associated to stripe rust resistance using a bulk-segregant approach for at least 70 individual genes in the 40 varieties. The SNP markers will be validated using the individual bi-parental mapping populations. The SNP markers for new resistance loci will be converted to KASP markers. New germplasm lines carrying new genes will be selected based on morphological plant types, stripe rust reactions, and molecular markers, and these lines will be deposited and registered in the ARS National Small Grain Collections.
